Appliance for supplying gas into a predetermined zone

ABSTRACT

A device for supplying gas into a predetermined zone of a roasting kiln rotating about its longitudinal axis. The device includes an annular collector externally enclosing the kiln and secured thereon. The collector is connected to a gas line and branch pipes of the collector to burners disposed in rows along the kiln. Mounted on the branch pipes are shutoff devices. Provided in the plane of rotation of the shutoff devices are stops: one for opening the cocks disposed at the inlet of the burners of its row into the predetermined zone of the kiln, and the other for closing the cocks disposed at the outlet of the burners from the predetermined zone of the kiln.

United States Patent APPLIANCE FOR SUPPLYING GAS INTO A PREDETERMINED ZONE 3 Claims, 2 Drawing Figs.

0.8. CI 263/33 Int. Cl F27b 7/00 Field otSearch 263/32, 33

Primary Examiner-John J. Camby AttorneyWaters, Roditi, Schwartz & Nissen ABSTRACT: A device for supplying gas into a predetermined zone of a roasting kiln rotating about its longitudinal axis. The device includes an annular collector externally enclosing the kiln and secured thereon. The collector is connected to a gas line and branch pipes of the collector to burners disposed in rows along the kiln. Mounted on the branch pipes are shutofi' devices. Provided in the plane of rotation of the shutoH devices are stops: one for opening the cocks disposed at the inlet of the burners of its row into the predetermined zone of the kiln, and the other for closing the cocks disposed at the outlet of the burners from the predetermined zone of the kiln.

MLJ@@;E@ 1, l 3 1] Patented May 25, 1971 APPLIANCE FOR SUPPLYING GAS INTO A PREDETERMINED ZONE The invention relates to apparatus used in the field of thermal treatment of bulk materials, and more particularly to apparatus for supplying gas into a predetermined zone of a furnace where oxidized iron ores are calcinated in order to reduce and further enrich them by a magnetic method.

Known in the prior art is an apparatus for supplying gas under a layer of ore into a rotating tubular oven or kiln, and being made as a number of burners secured to the furnace walls along the circumference, and communicating with the working space of the oven. Gas is supplied to those burners from a gas line through the collector envelopes contacting with the external surface of the rotating kiln. A collector is disposed under the kiln and is intended for supplying gas into the oven zone filled with a layer of material.

When the device is in operation, it is difficult to maintain airtightness at the points where the envelopes contact the rotating kiln surface; moreover, gas is supplied under pressure into the envelopes, and they are subject to wear by the kiln surface and the burners.

An insufficient airtightness between the envelopes and the kiln body may result in gas leakage, in contamination and pollution of the shop air with gas; also, it can render the shop atmosphere explosive.

Also known in the prior art is a kiln where the burners arranged in the working space of the kiln are connected to a gas line by means of a plurality of channels spaced on the refractory brickwork lining of the kiln and at different distances from the oven working space.

The supply of gas into test channels is carried out at the moment when the channels arranged in the kiln rotating portion coincide with the openings in the slide valve device and those of the gas line in the kiln immovable portion.

The provision of a plurality of channels in the oven lining presents some difficulties; for instance, their presence renders the lining less strong, makes their repair, inspection serviceability more difficult.

In addition, at the place of location of theslide valve device there is friction between the surfaces of the rotating and immovable portions of the kiln operating because of dust, gas and high temperatures, which, results in reducing the service life of the device intended for supplying gas to the predetermined zone of the kiln.

An object of the present invention is to eliminate the above disadvantages. Other objects and advantages of the invention will become more fully apparent from the following description thereof.

The principal object of the invention is to provide a device which is dependable in operation, simple to control, easily accessible for inspection, airtight (precluding the possibility of gas leakage and pollution of surrounding atmosphere by gas) and nonexplosive.

This object is achieved with the provision of a device for supplying gas into the predetermined zone of the kiln rotating about its longitudinal axis which comprises a collector communicating with a gas line and with burners, the latter communicating with the kiln working space. According to the invention, the collector is made annular, externally embracing the kiln, secured thereon and provided with branch pipes. Each branch pipe is connected to a group of burners arranged along the kiln and fitted with a shutoff device interacting with two stops when the kiln is rotating. One of the stops alternately opens each shutoff device to supply gas into each group of burners incorporated in the given zone of the kiln, whereas the other stop alternately closes the shutoff device after the group of burners has passed the specified zone of the kiln.

It is expedient that the shutoff devices in the present device or apparatus be made as two-way cocks with handles being essentially cross-shaped steer wheels, whereas the stops are essentially uprights to be vertically adjusted.

The nature of the present invention will become more fully apparent from a consideration of the following description of a device for supplying gas into a specified zone of the kiln, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a side elevation of the device according to the invention; and

FIG. 2 is a cross-sectional view of the same device, taken on line llll of FIG. 1.

The device for supplying gas under a layer of ore (as shown by a dotted line) into a predetermined zone of kiln 1 (HO. 1 and 2) comprises an annular tubular collector 2 complete with branch pipes 3 externally enclosing kiln 1. Each branch pipe 3 is connected to a group of burners-4 communicating with the working space of kiln l and arranged in rows along the kiln. Disposed on each branch pipe between annular collector and the group of burners 4 is a shutoff device 5 made as a two-way cocks with a handle being essentially a cross-shaped steer wheel 6. Provided on the side of annular collector 2 in the plane in which steer wheels 6 rotate, are stops 7 and 8 on uprights to be vertically adjusted due to their telescopic construction.

The present invention operates as follows:

Depending upon the speed of the kiln rotation, material, in this case iron ore, moves in the kiln, being thus in different positions, the specific position thereof determining dimensions of the specified zone for supplying gas under the layer of material being treated (shown by a dotted line).

In connection therewith, the uprights with stops 7 and 8, mounted in the plane of rotation of cross-shaped steer wheels 6, are vertically adjusted so that stops 7 and 8 engage steer wheels 6 during rotation of kiln l.

The direction of the kiln rotation is indicated by arrow A. The uprights are telescopic, and they are adjusted by being lowered or drawn apart. The stops provided at an appropriate height and distance, ensure the opening and closing of the shutoff devices at the right. times, in this case, of the two-way cocks.

At the inlet to the predetermined zone of the group of burners 4 disposed along the kiln and supplied with gas from one branch pipe 3, their steer wheel 6 interacts with stop 7 turning steer wheel 6 through an angle of and opening a cock for supplying gas to burners 4 disposed under the layer of material.

During rotation of kiln l, the group of burners 4 is displaced under the material, and before emerging from the predetermined zone the steer wheel 6 engages stop 8. Steer wheel 6 is again turned through 90 and thereby closes cock 5, thus stopping the supply of gas into the group of burners 4 emerging from the given zone of the kiln.

Cocks 5 of other groups of burners 4 are similarly switched over at their entry in and emergence from the predetermined zone of kiln.

According to other exemplary embodiments of the appliance, gate valves or dampers may be employed as shutoff devices; and this will result in a corresponding modification of the construction of the stops.

Experiments have shown the described device to be dependable in operation when supplying gas into the predetermined zone. of the kiln, airtight, simple in construction and easily accessible for inspection.

The appliance of the invention may be employed for the metallizing of ore pellets.

This device may be used to supply gaseous or liquid fuel into a rotary tubular oven.

Though the present invention is described in connection with its preferred embodiment, it is obvious that there may be allowed variants and modifications thereof, which do not depart from the idea and scope of the invention, as defined in the appended claims.

lclaim:

l. A device for supplying gas into a predetermined zone of a kiln rotating about its longitudinal axis, comprising: a gas line of said kiln; an annular collector, branch pipes, said annular collector being provided with said branch pipes, said branch pipes communicating with said gas line and externally enclosing said kiln and being secured thereon; burners communicating with the working space of said kiln and arranged along said working space in rows, each of said burners being connected to a branch pipe of said annular collector; shutoff devices mounted on said branch pipes of the annular collector for the intermittent closing of a gas flow to said burners; two stops disposed in the plane of rotation of said shutoff devices and interacting therewith during rotation of said kiln to alternately open and close each of said shutoff devices to supply gas into 

2. A device according to claim 1 wherein the said shutoff device is a two-way cock with a handle made as a cross-shaped steer wheel, said stops being made as vertically adjustable uprights.
 3. A device according to claim 1, wherein said stops comprises telescoping segments for adjustability in height. 